Vulnerability · Published Aug 19, 2026 · Assigned by GitHub_M

CVE-2026-49253electerm: Path Traversal in Zmodem and Trzsz Download Filename Handling

High 7.1

In plain English

A high-severity path traversal in electerm from electerm. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 38% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.1High
Exploit odds (30 days)0.4%top 61.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

electerm is an open-sourced terminal/ssh/sftp/telnet/serialport/RDP/VNC/Spice/ftp client. Prior to 3.11.11, electerm uses remote-supplied filenames directly with path.join() while receiving Zmodem and Trzsz transfers. In src/app/server/zmodem.js, prepareReceiveFile() joins the filename to the user-selected save path, and in src/app/server/trzsz.js, getUniqueFilePath(), the openSaveFile() callback, and the savedFilePaths mapping construct destinations without sanitization. A malicious SSH server or remote shell can provide a filename containing traversal components such as ../escaped.txt or ../../.bashrc. When the victim accepts the transfer and selects a download directory, electerm can write outside that directory and overwrite files accessible to the desktop user, potentially changing sensitive configuration or impairing availability. This issue is fixed in version 3.11.11.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
npmelecterm3.11.11GHSA-38j7-23hf-9mhc

Affected products (as reported)

VendorProductVersions
electerm electerm < 3.11.11

Weakness: CWE-22 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:L

References